drm/i915: Add some debug breadcrumbs to connector detection

Try to decypher detection failures is a little tricker at the moment as
the only indicator of progress is when output_poll_execute() tells us
the result after the connector->detect() has run. This patch adds a
telltale to the start of each detect function so that we can track
progress and associate activity more clearly with each connector.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 3acec8c..0c0d4e8 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -613,6 +613,10 @@
 	enum drm_connector_status status;
 	struct intel_load_detect_pipe tmp;
 
+	DRM_DEBUG_KMS("[CONNECTOR:%d:%s] force=%d\n",
+		      connector->base.id, drm_get_connector_name(connector),
+		      force);
+
 	if (I915_HAS_HOTPLUG(dev)) {
 		/* We can not rely on the HPD pin always being correctly wired
 		 * up, for example many KVM do not pass it through, and so